Fastener construction



Jan. 2o, 1942.- J.`R, BIGIMELL` ETAL 2,270,403

FAS TENER CNSTRUCT ION Filed sept. 22,l 1941 Patented jan. 20, 1.942Y

FASTENER CONSTRUCTION James` R. Bigneli and Russell C. Huntoom, San

Diego, Calif., assignors to Solar Aircraft Company, San Diego, Calif., a corporation of Calilllia Appueeuen september z2', 1941, serial Ne. 41-1,sss 2 claims. (CI. z4221)` `This invention relates to detachable fasteners of the Dzus" type disclosed in United- States patent to Dzus, No.1,955,740, issued April 24,

1934. which are'in general use for securing parts,

l particularly sheet metal parts, together.

An object of the invention is to simplify and reduce the cost of installing and repairing Dzus fasteners.

The manner in which this object is attained will be explained with reference to the drawing, in which Fig. 1 is a plan view of a pair of sheet metal parts secured together by a Dzus fastener in accordance with the invention;

Fig. 2is a detail section in the plane II-II of Fig. 1; and

Fig. `3 is a view looking at theunderside of Fig. 2A withportions broken away.

I Referring to Figs. l and 2, there is shown two Y sheet metalparts I and II, respectively, which are securedtogether by a Dzus fastener, the essential elements of which include a screw-cam velement I2 on sheet I0 and a spring member I3 on the sheet II. f'

As shown, the screw-cam element I2 is of the flush type, having a beveled head fitting into a dimple provided therefor in the sheet II). It is retained in the sheet III byl the edge I4 of the aperture therein, which extends into an annular groove i5 in the .screw-,cam element IZ at the junction ofthe head-of the'screw-cam element with the shank I6 thereof.

The spring element I3 has a transverse portion" I1 extending through an opening provided therefor in the shank I6 of the screw-cam member,

the opposite ends of the spring' member being secured to the plate Il. A The opening in the shank I 6 of the screwcam member is so-shaped as to make interlocking connection with the transverse portion I1 of the spring-element in response to rotation of the screw-cam member through approximately 90. The particular shape of the 'opening does not constitute a part of the present invention, and need not be discussed further. Full information relative thereto may be obtained from the catalog of the Dzus Fastener Company, Inc:

Our construction as shown in` Figs. l, 2 and 3,

-diifers from the conventional Dzus fastener only in the,l manner of attaching the spring member I3 to the plate II. Heretofore these springs have been riveted or bolted to their associated sheet members. Such construction has the disadvantages that lt is very difficult, and in many cases impossible, to replace a broken spring. VIt has the further disadvantage that the rivet holes must be very accurately aligned with respect to the v screw-cam element, which requires expensive punches and other tools for fabrication.

In accordance with the present invention, we

support the spring element I3 on theplate II `v Without the use of screws, bolts, or rivets, and

at the same time support it with limited lateral movement so that it is self-aligning.

Thus We provide on the underside of the sheet member II, a stamped retaining plate IB which 1 is secured to the sheet I I, preferably by spot- `welding. The stamping' I8 has a central aper-4 ture I9 adapted to align with the opening in the plate I0 and is dimpled around the opening to fit against the corresponding dimpled portion of the sheet Ill. The'at portion of the stamping I8 may be oval in outline, as clearlyV shown in Fig. 3, and has cut-out'portions 20 of approximately semi-circular shape. Immediately beyond each cut-out portion 2D the'plate is pressed out to define with the juxtaposed portion of the plate II, pockets into which the coiled ends 22 of the spring member I3 are received and retained. The coiled` portions 22 of the spring member are of slightly smaller diameter than the pockets 23 so that they can move laterally to a limited extent to align themselves with the screw-cam element.

The spring member I3 has suflicient resilience to 'permit it to be deformed sufficiently to insert the ends in the pockets 23. Y

Our construction not only has the obvious ad-,

vantage of permitting ready insertionV of the springs, either originally or in service, but it is also very inexpensive and isbetter adaptedv to use with thin sheet metal than are rivets, screws, and `the like. The stampingl functions as a .reinforcement which is very useful on thin sheet metal adjacent its point of attachment totanother member.

For the purpose of explaining the invention l a particular embodiment thereof has been described in substantial detail. However, `it will be Y obvious to those skilled in the art that numerous departures from the exact construction shown can be made without departing from the invention, and the latter is, therefore, to be limited only to the extent set forth in the appended claims. f

We claim: Y

1. In a Dzus fastener for securing two members together and including a screw-cam element adapted to bear against one of said 4members and i a cooperating spring' rod element adapted to bear against the other member, means for securing said spring rod element to said other member, comprising: an auxiliary plate mem- Y ber secured to the face of said other member and forming therewith pockets for receiving the' ends cf said spring rod element.

2. A device as described in claim 1, in which said spring'rod elementrterminates at the end in l 

